1. Field of the Invention
This invention relates generally to tape drive units intended for maintaining data written on a magnetic tape and to recording media for use therewith.
2. Description of the Related Art
A type of recording media is known in which data can be written only once in a particular recording area. Since the recording media of this type are used as additionally writable or read-only recording media, they are called, for example, write only read many or WORM. As a WORM recording medium, a type of optical disk called a CD-R or compact disk recordable is known, in which data are written by physically forming pits on the disk recording surface. Accordingly, CD-Rs excel in data protection because it is impossible to change the data once it has been written.
A so-called tape streamer drive has recently been in wide use as a drive unit for writing/reading digital data to/from a magnetic tape. This tape streamer drive can have a large recording capacity of approximately several dozen to several hundred gigabytes, although the capacity varies according to the length of the recording tape in the tape cassette. Accordingly, the tape streamer drive has various uses, such as a backup of data written on a hard disk of a computer. The tape streamer drive is also suitable for storing image data, which typically involves a large amount of data.
The magnetic tape has a recording capacity greater than that of a CD-R, and this reduces the cost per bit unit for the whole recording capacity of the recording medium. Thus, it is possible that the tape cassette can be used as a WORM recording medium.
Data written on the magnetic tape, however, may be erased if some faulty operations are performed when the tape cassette is loaded into the tape drive unit. The data written on the magnetic tape can also be intentionally rewritten. Accordingly, there is a problem in that the magnetic tape does not excel in the protection of important data.
Accordingly, it is an object of the present invention to provide an apparatus and record medium for use in a data streamer that can eliminate the above-noted defects inherent in the prior art.
According to one aspect of the present invention a tape drive unit includes a tape drive in which, when a tape cassette including a magnetic tape is loaded, the tape drive runs the magnetic tape and writes/reads information to/from the magnetic tape; a memory drive in which, when the loaded tape cassette includes a memory for storing management information for managing the writing/reading of information to/from the magnetic tape, the memory drive can read or write the management information by performing predetermined communication processing with a memory; a use-recognition-information detecting circuit for detecting, from the memory, use-recognition information designating a use for the tape cassette; and a controller in which, when a predetermined operation command is supplied, the controller means performs an operation on the magnetic tape, based on the use-recognition information.
According to another aspect of the present invention, a tape drive unit includes a tape drive in which, when a tape cassette including a magnetic tape is loaded, the tape drive runs the magnetic tape and writes/reads information to/from the magnetic tape; a memory drive in which, when the loaded tape cassette includes a memory for storing management information for managing the writing/reading of information to/from the magnetic tape, the memory drive can read or write the management information by performing predetermined communication processing with the memory; a first identification-information detecting circuit for detecting identification information of the tape cassette stored in the memory; a second identification-information detecting circuit for detecting identification information of the tape cassette stored in the magnetic tape; an identification-information determining circuit for determining whether the two types of identification information, detected by the first and second identification-information detecting circuits, coincide with each other; and a controller for executing only a particular operation based on a result of the determination by the identification-information determining circuit.
In another aspect of the present invention a record medium is provided that includes a tape cassette including a magnetic tape; and a memory built into the tape cassette, which stores management information for managing writing/reading to/from the magnetic tape; the memory stores use-recognition information designating a use for the tape cassette. In another example, identification information of the tape cassette are stored in the memory and the magnetic tape.
Since a tape drive unit of the present invention controls operations relative to a tape cassette based on use-recognition information, the tape drive unit inhibits the execution of processes, such as the erasing and rewriting of written data requiring protection, thereby preventing the content of the data from being changed.
Only when identification information on a magnetic tape and identification information in a memory coincide with each other, are particular operations allowed, such as reading from and writing to the magnetic tape. This enables protection of written data in a tape cassette in which, for example, a magnetic tape or memory is exchanged.
Since a recording medium of the present invention stores use-recognition information for instructing a memory regarding a use for which a tape cassette is adapted, the recording medium can inform the use for the recording medium to a tape drive unit into which the tape cassette is loaded.
Moreover, since a memory and a magnetic tape store identification information such as a tape cassette""s serial number, the correspondence between the memory and the magnetic tape, which are included in the same tape cassette, can be established. Thereby, when identification information detected from the memory and identification information detected from the magnetic tape do not coincide, a drive unit into which a tape cassette is loaded can restrict writing and reading operations.